Fix false positive for PreferTestCleanupOverDispose on non-test classes (#4380)

Author: Youssef1313

src/Analyzers/MSTest.Analyzers/PreferTestCleanupOverDisposeAnalyzer.cs

@@ -40,22 +40,28 @@ public override void Initialize(AnalysisContext context)
 
         context.RegisterCompilationStartAction(context =>
         {
-            if (context.Compilation.TryGetOrCreateTypeByMetadataName(WellKnownTypeNames.SystemIDisposable, out INamedTypeSymbol? idisposableSymbol))
+            if (context.Compilation.TryGetOrCreateTypeByMetadataName(WellKnownTypeNames.SystemIDisposable, out INamedTypeSymbol? idisposableSymbol) &&
+                context.Compilation.TryGetOrCreateTypeByMetadataName(WellKnownTypeNames.MicrosoftVisualStudioTestToolsUnitTestingTestClassAttribute, out INamedTypeSymbol? testClassAttributeSymbol))
             {
                 INamedTypeSymbol? iasyncDisposableSymbol = context.Compilation.GetOrCreateTypeByMetadataName(WellKnownTypeNames.SystemIAsyncDisposable);
                 INamedTypeSymbol? valueTaskSymbol = context.Compilation.GetOrCreateTypeByMetadataName(WellKnownTypeNames.SystemThreadingTasksValueTask);
-                context.RegisterSymbolAction(context => AnalyzeSymbol(context, idisposableSymbol, iasyncDisposableSymbol, valueTaskSymbol), SymbolKind.Method);
+                context.RegisterSymbolAction(context => AnalyzeSymbol(context, testClassAttributeSymbol, idisposableSymbol, iasyncDisposableSymbol, valueTaskSymbol), SymbolKind.Method);
             }
         });
     }
 
-    private static void AnalyzeSymbol(SymbolAnalysisContext context, INamedTypeSymbol idisposableSymbol, INamedTypeSymbol? iasyncDisposableSymbol,
+    private static void AnalyzeSymbol(
+        SymbolAnalysisContext context,
+        INamedTypeSymbol testClassAttributeSymbol,
+        INamedTypeSymbol idisposableSymbol,
+        INamedTypeSymbol? iasyncDisposableSymbol,
         INamedTypeSymbol? valueTaskSymbol)
     {
         var methodSymbol = (IMethodSymbol)context.Symbol;
 
-        if (methodSymbol.IsAsyncDisposeImplementation(iasyncDisposableSymbol, valueTaskSymbol)
-            || methodSymbol.IsDisposeImplementation(idisposableSymbol))
+        if (methodSymbol.ContainingType.GetAttributes().Any(x => x.AttributeClass.Inherits(testClassAttributeSymbol)) &&
+            (methodSymbol.IsAsyncDisposeImplementation(iasyncDisposableSymbol, valueTaskSymbol)
+            || methodSymbol.IsDisposeImplementation(idisposableSymbol)))
         {
             context.ReportDiagnostic(methodSymbol.CreateDiagnostic(Rule));
         }

test/UnitTests/MSTest.Analyzers.UnitTests/PreferTestCleanupOverDisposeAnalyzerTests.cs

@@ -10,6 +10,23 @@ namespace MSTest.Analyzers.Test;
 [TestGroup]
 public sealed class PreferTestCleanupOverDisposeAnalyzerTests(ITestExecutionContext testExecutionContext) : TestBase(testExecutionContext)
 {
+    public async Task WhenNonTestClassHasDispose_NoDiagnostic()
+    {
+        string code = """
+            using System;
+            using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+            public class MyNonTestClass : IDisposable
+            {
+                public void Dispose()
+                {
+                }
+            }
+            """;
+
+        await VerifyCS.VerifyCodeFixAsync(code, code);
+    }
+
     public async Task WhenTestClassHasDispose_Diagnostic()
     {
         string code = """